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A087743
Numbers n >= 3 with property that the remainder when n is divided by k (for 3 <= k <= n-2) is not 1.
0
3, 4, 5, 6, 8, 12, 14, 18, 20, 24, 30, 32, 38, 42, 44, 48, 54, 60, 62, 68, 72, 74, 80, 84, 90, 98, 102, 104, 108, 110, 114, 128, 132, 138, 140, 150, 152, 158, 164, 168, 174, 180, 182, 192, 194, 198, 200, 212, 224, 228, 230, 234, 240, 242, 252, 258, 264, 270
OFFSET
1,1
COMMENTS
More generally, let prime_Y consist of the numbers n >= 2+Y which never yield a remainder of Y when divided by any number from 2+Y to n-Y-1. Prime_0 are the usual primes, A000040. This sequence gives prime_2.
FORMULA
P[n, Y] = P[n-1, Y] for most terms where P is a Boolean array of numbers n and Y their order of primeness: if P[n, Y] then n is a prime of order Y
MATHEMATICA
Select[Range[3, 500], Count[Table[Mod[#, k], {k, 3, #-2}], 1]==0&] (* Harvey P. Dale, Dec 17 2011 *)
CROSSREFS
Sequence in context: A130788 A376601 A288819 * A073568 A094576 A103103
KEYWORD
nonn
AUTHOR
Chas A Guderjahn (chasag(AT)aol.com), Oct 01 2003
EXTENSIONS
More terms from Harvey P. Dale, Dec 17 2011
STATUS
approved